By analyzing the spooky abandoned "houses" of mucus-weaving sea creatures, Monterey scientists have shed new light on two lingering mysteries -- how creatures in the deep sea get food, and how the ocean absorbs carbon molecules that might otherwise contribute to global warming.

Despite its name, the "giant larvacean" is a sea creature that is only about 2 inches long. But it spins gossamer-like nets of mucus -- which in photos resemble glistening parachutes and balloons -- up to a few feet wide, scientists at the Monterey Bay Aquarium Research Institute (MBARI) at Moss Landing explain in today's issue of the journal Science.

Those mucus nets act like catchers' mitts, grabbing descending organic particles -- say, fecal pellets from fish -- that then provide nourishment to the giant larvacean. The creature is technically known as Bathochordaeus charon and was discovered 107 years ago.

But after a day or so, the net's filters clog up, rendering them useless. Then the creature abandons the net, which quickly sinks to the ocean floor. The creature then spins a new net, and the cycle continues.

In their study published today, Bruce H. Robison and two colleagues, Kim R. Reisenbichler and Rob E. Sherlock, describe how they used remotely operated submersible vehicles, or ROVs, to study sinking larvacean nets -- also known as houses or "sinkers" -- in Monterey Bay.

By analyzing hundreds of hours of videotape from the ROVs, they calculated that sinkers deliver almost as much food and carbon to the ocean floor as do the falling organic particles known as "marine snow" -- so named because in the floodlights of diving submersibles, the descending material resembles a gentle snowfall.

That finding verifies an idea previously proposed by other scientists, that the sinkers provide a way to explain how deep-sea creatures remain nourished.

According to an MBARI statement, they found that the sinkers provide a food source that is "more than adequate to feed all those hungry deep-sea animals."

The MBARI findings also elucidate one of the major ways that the ocean processes carbon molecules, which are abundant in organic materials such as the larvacean houses, and becomes -- as scientists have long known -- a sort of burial ground for the carbon that would otherwise remain in the atmosphere.

In essence, one of the ways the ocean absorbs carbon is in the form of the larvacean houses, then it stores that carbon on the ocean floor.

Were this not occurring, carbon might remain in the atmosphere in the form of carbon dioxide, a major "greenhouse gas" that drives global warming.

By observing hundreds of hours of videotape, the scientists concluded that every square meter of seafloor received an average of four "sinkers" per day. They also captured sinkers and chemically analyzed them in the lab to measure their carbon content and found it to be unusually high.

The MBARI work is a culmination of ideas that go back for decades.

Woody Allen once joked that the nature is just "a giant restaurant" -- but where the food comes from isn't always clear. For decades, scientists scrutinized the jungles of creepy creatures that swim and crawl over the dark ocean bottom and wondered: How did they survive, considering the apparent scarcity of food down there?

There simply isn't enough marine snow falling to the ocean floor to feed all the creatures down there. Nor can they survive simply by eating each other.

Over the years, various theories have been kicked around -- that the deep-sea creatures lived off sunken dead whales, or off organic materials washed into the sea from the land.

A third of a century ago, the marine scientist Alice L. Alldredge reported how creatures called planktonic copepods fed on "abandoned larvacean houses."

In a 1972 article for the journal Science, Alldredge -- who now chairs the department of ecology, evolution and marine biology at UC Santa Barbara, wrote that "the abundance of larvacean houses in the open ocean indicates that they are important in pelagic food webs and as a source of particulate organic matter."

In an interview, Sherlock stressed that the MBARI work builds on the work by Alldredge and by two other researchers, Bill Hamner of UCLA and Mary Silver of UC Santa Cruz, "all of whom have made important contributions to the study of mesopelagic mucus -- not the least of which is the need to get out and observe it firsthand."